In the web offset printing process, a continuous web of paper is transported through a printing press. Near the beginning of the press, one or more printing units may apply ink to the web to repeatedly create a pattern, or impression, of text and images. At the end of the press, a web conversion machine, such as a folder, may be used to cut and fold the web into signatures.
To convert a web into signatures, the web may be slit into ribbons, and the ribbons may be redirected by lead rolls and angle bars into a stacked configuration for subsequent folding and cutting. Ribbons may be transported with each edge being an equal distance above the floor or with the ribbons traveling on-edge so that one edge is above the other. With on-edge ribbon transport, it can be more difficult to install the ribbons in the machine, and the ribbons may be more likely to fall to the floor when they break.